public class Example4_5 {
  public static void main(String args[]) {
  Rect ractangle=new Rect();
  ractangle.width=109.87;
  ractangle.height=25.18;
  double area=ractangle.getArea();
  System.out.println("矩形的面积:"+area);
  Lader lader = new Lader ();
  lader.above=10.798;
  lader.bottom =156.65;
  lader.height=18.12;
  area = lader.getArea();
  System.out.println("提醒的面积:"+area);
}
}

